A war, a spreading disease like a plague, or natural disasters.
Answer:
Male and female gametes are formed and combine in a moist environment to form a zygote.
Explanation:
The gametophyte of a moss plant bears male sex organ antheridia and female sex organ archegonia.
Sperms, the male gametes are produced within antheridia and the eggs are produced in archegonia.
Both the antheridia and archegonia may be produced on the same gametophyte or separate gametophytes depending on the type of moss.
Haploid sperms are released from the antheridia and with the help of moisture, it reaches to a haploid egg in an archegonium. The female gamete or egg is fused with sperm to produce a diploid zygote.
The zygote later develops into the diploid sporophyte.
Build several models of his tree house out of different materials, and see which model holds up best to wind, water, and ice.
Metamorphic rock because the original rock is subjected to heat and pressure, causing profound physical or chemical change.